Tervuren Square

how to articulate the conversion of a tertiary site into a sustainable residential complex oriented towards a garden in the interior of the block

project characteristics

Strategically located along the Avenue de Tervuren near Square Montgomery (Woluwe Saint Pierre), the site of this programme – occupied by the 12.000 m² of 3 tertiary buildings built in 1975 (*) – traverses the block to include a building on the Avenue de Tervuren side, a building on the rue du Collège Saint Michel side, and a central building. Each of these buildings was the subject of an in-depth study to determine the most appropriate approach to its environment

programredevelopment project (renovation/reconstruction) of an urban tertiary site - formerly occupied by INAMI- into a mixed residential & office project
clientBelfius Immo • BPI Real Estate Belgium • Burco Europe
addressavenue de Tervuren 249-255 • rue du collège Saint-Michel 17-23, 1150 Woluwe-Saint-Pierre
building typelive • work
statusunder construction
expertisesarchitectureinterior architecturelandscape designproject managementconstruction managementfeasibility studiesprogramming
size+/- 12.000 m²
team• client: Belfius Immo • BPI Real Estate • Burco Europe
• architect : assar
• special technologies engineer: Boydens
• stability engineer: Lemaire ingénieur
•general contractor: BPC
• acoustics: Venac • Sweco

The development of the site therefore favours a specific approach for each building, rather than a generalised intervention that would not match the real potential of the site. The future development will therefore include a major renovation of most of the building on the Avenue de Tervuren, a renovation of the central building called the Loft, and a demolition-reconstruction for the part located on the Rue du Collège Saint Michel.

This approach will, in particular, enable the reuse of the existing concrete structure of the Avenue de Tervuren building for the construction of 52 flats and 3 office spaces on the ground floor.

The demolition-reconstruction of the building on rue du Collège Saint Michel will provide the site with 29 new residential units and an additional service area on the ground floor.
The new volume is intended to restore the adjoining alignments and to provide the rue du Collège Saint-Michel with a new residential building of quality, that meets all current requirements in terms of comfort.

The renovation of the central “Loft” building will create new divisible tertiary spaces and will have an intensive green roof.

(*) former INAMI site (National Institute for Sickness and Disability)

The basements will be renovated to provide 104 parking spaces for motorised vehicles. Mindful of current environmental issues, the project places special emphasis on promoting sustainability, circularity, and biodiversity in an urban setting.

An inventory was carried out to determine which materials and elements of the of the existing building were to be reused.
The project therefore incorporates various elements to give them a second life. For example, the façade stone will be reinstalled in the main common areas as wall cladding, the façade maintenance gratings will be adapted and used as partitions/rails in the stairwells and the door leaves will be partly recovered for installation in the cellars. In terms of the surroundings, the blue stone already present on the site will be recovered and used to create the new garden steps.

The project also responds to the energy and environmental ambitions clearly stated by the project owner.

In general, the project emphasises  the promotion of biodiversity in this urban setting. The creation of green roofs on all the buildings and the demolition of part of the central building in order to provide a more generous open area are part of an overall architectural and urban planning approach on the scale of the block aimed at providing a qualitative green environment for both the residents and the operators of the tertiary zones.

The interior of the block, which will be accessed via Avenue de Tervuren, will therefore be laid out as green space and 3 private gardens. On the street frontage, the setback zone will be developed in the same way.

In the same spirit of the greening of the site, the project favours the use of indigenous species and treats the garden according to different moods, also taking into account their orientation.

In terms of energy, the land potential of the site has enabled the technologies to be oriented towards geothermal energy by coupling it with a cogeneration and heat pumps system. The potential overheating of the southern façades is directly managed by the architecture, in the form of loggias or sometimes by balconies, providing the interior spaces with fully integrated sun shading.

Water management is also optimised by storing rainwater in several tanks. These supply the gardening maintenance taps for the various green spaces of the project.

architecture & design

The mixed nature of project assets is reflected in the creation of 3 different buildings and an interior garden. Each building provides a specific response to the typology of the street or the space with which it is incorporated. These three buildings, with their own functionalities, retain their autonomy, while being interconnected via the collective interior garden.

Four elements structure this programme:

  • “Tervuren Square” (ground floor + 8): residential+offices
  • the “Loft” (ground floor): offices
  • “17 College” (ground floor + 5): residential+offices
  • the interior garden


As this is a “city centre” project, a well-conceived pedestrian access strategy is fundamental. In order to create a coherent link between the programme and the public domain, each building is provided with a clear and independent access from the road. Tervuren Square is accessible from the Avenue de Tervuren. A generously proportioned carriage-type entrance  (with access control) serves the two entrance halls for the residential units. This passageway also serves two office areas, one of which is a duplex (ground floor – first floor). A third office area on the ground floor is directly accessible from the Avenue de Tervuren via an independent access.

The “Loft”, located at the heart of the project, is also accessible via the ‘passage cocher’/carriage entrance. Its entrance is located in the axis of the opening and offers views from the public domain.

The “17 Collège” has two access halls, which are situated in a less frequented area, from the rue du Collège Saint-Michel.


As a programme in a mid to high-end residential sector, it requires the use of quality materials in keeping with its built environment.
A light natural stone is used for the main mass of the building, while a warmer tone is used as a second reading for the ornamental frames, reveals, and balustrades. This bronze colour is also used in the treatment of the project’s coping, but above all on the entire party wall. This colour blends in perfectly with the vegetation in the foreground, integrating the party wall into the planted decor.

Also keeping in mind this perspective of ensuring the quality of materials, the origin of the materials is also a major guiding principle for the project. The general contractor is thus contractually obliged to propose materials of local (national) and/or European origin.


In order to respond to the current and future urban context, the programme matches its residential provision with innovative concepts that reinforce its urban character and respond to the evolution of urban living:

  • intelligently designed cabinets for the delivery of parcels purchased online are provided near the entrance halls
  • all the underground parking spaces can be equipped with electric car charging sockets, directly connected to private meters


energy performance & certification
  • PEB A+
  • geothermal-heat pump
  • circularity